Vol. 57.] UPPER GEEENSAND AND CHLORITIC MARL OF WILTSHIRE. 11^ 



made up of quartz-grains, with a few scattered grains of glauconite 

 and some calcareous particles which effervesce when it is treated 

 with acid. At this end of the quarry only 5 or 6 feet of the sand 

 is usually exposed, but it has been dug to a depth of 9 or 10 feet 

 more without showing any marked change. 



The beds above described rise westward, the higher strata 

 gradually disappearing, till at the western end of the quarry the 

 section seen is : — 



Feet 



Surface-soil ^ 



Rubble of 'popplestones' and phosphatic nodules embedded 



in sand 4 



Fine-grained sands, with layers of chert and of calcareous 



sandstone, seen for 17 



~m 



The most remarkable feature in this section is undoubtedly the 

 curious irregular bed which encloses the ' popplestones ' and the 

 marked break which occurs at its base. Equally curious is the 

 absence of any bed to correspond with the sand, which, at Maiden 

 Bradley and Rye Hill, intervenes between the Cornstones and the 

 Chloritic Marl. It would appear that the sand with ' popple- 

 stones ' here takes the place of the Cornstones and the overlying 

 sand which is so rich in fossils farther north, for very many of the 

 same species occur among the 'popplestones.' At any rate this 

 bed seems to form a natural base to the Chloritic Marl, while the 

 sand below it seems to fall more naturally into the underlying 

 Upper Greensand. 



Manor Farm, Mere. 



There is one other exposure near Mere which is worthy of mention, 

 because it suggests the existence of a flexure of the beds at this 

 locality, and the possibility of a small inlier of the beds at the 

 junction of Chalk and Upper Greensand to the north of Mere. A 

 small pit has been opened in the field west of Manor Parm, 

 and about J mile north-north-east of Dead-Maid Quarry ; the 

 hard Chloritic Marl is here close to the surface, and has been 

 quarried for use as a rough building-stone, but the section has not 

 been carried through it into the ' popplestone '-bed. There is no 

 appreciable dip, and near the opening is a watercourse (dry in 

 summer) running south-eastward to Mere. In this watercourse are 

 stones like those which occur in the sand below the ' popplestones '; 

 but at the ' Wellhead ' spring north of Mere there is Chalk-Marl 

 down to the spring-level. 



It will be remembered that in Dead -Maid Quarry the beds are 

 dipping eastward at an angle of about 5° ; this, if continued, should 

 carry the Chloritic Marl well below Mere. Probably the dip i& 

 really south-easterly ; but even so, as the level of the surface at 

 Dead Maid is about 370 feet and that at the other pit is about 380, 

 the Chloritic Marl could hardly be at the surface at the latter place, 

 unless it was brought up by a local anticlinal flexure. The 



Q. J. G. S. No. 225. i 



